"They were demanding to speak with a ranger. They were seriously worried that the calf was freezing and dying," said Karen Richardson, one of several parents chaperoning a group of fifth-graders on a field trip.

The website quoted another parent who told the tourists to remove the bison from their car, warning they could be in trouble.
"They didn't care," he said. "They sincerely thought they were doing a service and helping that calf by trying to save it from the cold."